Why hasn't The Hague/International Criminal Court ever gone after any of the Kims of North Korea?

Yeah,there are/were plenty of other dictators they could have pressed cases/charges against but maybe I'm just not up to speed on something. I thought this organization went after big fish like dictators and generals. Am I missing something?
Answers

Nancy

they tend to commit their atrocities within their own borders.

Nate

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Gerg

"They tend to commit atrocities within their own borders." That means nothing because so did Liberian Charles Taylor.